Contact plug



Feb. 20, 1940. I w HERMAN 2,191,384

CONTACT PLUG Filed May 21, 1935 Patented Feb.- 20, 1940.

1 UNITED STATES CONTACT PLUG William P. Herman, Bridgeport, Com,assignor to Electrix Corporation, a corporation of h Rhode IslandApplication May 21, 1935, Serial No. 22,506

8 Claims.

My present invention relates to the electrical art, and has particularreference to contact plug constructions.

It is the principal object of my invention to devise a plug constructionthat is readily molded, and is adapted to receive the prongs from eitherend.

It is a further object of my invention to provide a positive lockbetween the plug and the permanently retained in the plug afterinsertion therein.

It is an additional object of my invention to utilize a novel moldconstruction and a novel molding operation for obtaining prong lockrecesses in the plug body.

With the above and other objects and advantageous features in view; myinvention consists of a novel contact plug construction, more fullydisclosed in the detailed description following,

in conjunction with the accompanying drawing,

and more specifically defined in the claims appended thereto.

In the drawing,

Fig. 1 is a perspective view of the novel contact plug;

Fig. 2 is a section thereof, on the line 22 of F s- Fig.3 is a sectionthereof, on the line 3--3 of Flg. 2;

Fig. 4 is a perspective view of one contact P o Fig. 5 is a perspectiveview of the'end disk;

. Fig. 6 is a bottom plan view of Fig. 3; Fig. '7 is a sectional detailshowing the lead connection;

Fig. 8 is a sectional perspective showing the locking of the prongs onthe plug body; and- Figs. 9 and 10 are views of the mold dies, showingthem in closed and open positions.

It has been found desirable to construct acontact plug which is moldedto provide recesses for receiving contact prongs or blades and to lockthe prongs in place, the prongs being insertable from either end. Itherefore utilize a body mold of standard type, but including spacedtongues in the upper and lower dies which are shaped to contact and formlock recesses in the body, and to move outwardly after the molding 60operation, whereby prong channels are provided at each end of the plugbody.

Thus, referring to Figs. 1 to 8, the contact plug 10 includes a plugbody ll, preferably of rubber, and two contact prongs l2, l3, the plugbodyhavingabase l4 recessedasat Lands.

prongs, whereby the prongs are substantially neck portion l6 having agenerally rectangular recess l1, and a central cable passageway l8extending between the recesses. Two spaced aligned slot passageways I9,20 are provided, each including end sections 2|, 22, and an in- 6termediate restricted slot passageway 23; short wire channels 24, 25communicate the central cable passageway with the slot passageways I9,

The contact prongs or blades are alike, and 0 preferably of brass, andinclude a shank 26, a triangular tip 21, and a connecting neck portion28 of small diameter. The shank is preferably cut or rounded asindicated at 29 at the end, and I has an opening 30 adjacent the neckportion to I receive a wire end. The contact prongs, or blades, see Fig.4, are thus of rectangular shape, and are provided with an intermediaterectangular portion, at the head end, which has laterally extending lockportions or shoulders for en- 20 gaging the spaced lock shouldersprovided in the slot passageways.

Although the prongs may be inserted in the plug body from either end,they are preferably inserted from the base end, the wire ends being 25first passed through the openings 30, see Fig. '7, whereby the tips 21,pass through the restricted slot passageways 23 and lock in the endsections 2|, see Fig. 8, the wire ends entering the slots 24, 25 andbeing locked as shown in Fig. 30 '7. An end disk 31, see Fig. 5,provided with spaced slots 32, 33, is passed over the shanks l2, andseats in the recess I5, which preferably has its periphery slightlybevelled to lock the end disk in place. The slot passageways thus 35comprise flat slots, which as illustrated in the drawing, arerectangular linear slots of narrow width.

The plug body is molded in the usual manner, with standard molds; theupper and lower dies 40 are, however, provided with tongues 35, 36 whichhave stepped ends 31, 38, whereby the tongues permit molding of therestricted slot passageway 23, and are withdrawn as shown in Fig. 10when the dies are separated. 45

The plug body is thus readily molded of resilient rubber or the like,and the contact prongs 'or blades are readily inserted and when insertedare locked in place. The novel construction is inexpensive tomanufacture, is readily assem- 5o bled, and the prongs cannot becomeloose or withdrawn when subjected to ordinary use.

Although I have described one specific embodiment of my invention, it isobvious that changesinthesizeoftheparts,inthematerials used, and in therelative arrangement of the cooperating portions, may be made to suitthe requirements for diiferent contact plug designs, without departingfrom the spirit and the scope of the invention as defined in theappended claims.

I claim:

1. In a contact plug construction, a plug body of resilient materialhaving a flat slot passageway therethrough, said passageway havingintegral spaced separate parallel portions projecting towards each otherto form a restricted slot passageway intermediate the ends of said fiatslot passageway, and a flat contact prong seated in said fiat slotpassageway and extending in alignment therewith, said contact pronghaving a reduced portion intermediate its ends interlocking with therestricted slot passageway portions.

2. In a contact plug construction, a plug body of resilient materialhaving a fiat slot passageway therethrough, said passageway havingintegral spaced separate parallel portions projecting towards each otherto form a restricted slot passageway intermediate the ends of said flatslot passageway, said projecting portions having shoulders at each endthereof, and a flat contact prong seated in said fiat slot passagewayand extending in alignment therewith, said contact prong having aportion of a cross section corresponding to said restricted passagewayintermediate its ends, and interlocking with the shoulders on thepassageway portions.

3. In a contact plug construction, a plug body of resilient materialhaving a central cable opening and spaced flat slot passagewaystherethrough, said passageways each having integral spaced separateparallel portions projecting towards each other to form a restrictedslot passageway intermediate the ends of said flat slot passageway, saidprojecting portions having shoulders at each end thereof, and a fiatcontact prong seated in each fiat slot passageway and extending inalignment therewith, each prong having a portion of a cross sectioncorresponding to said restricted passageway intermediate its ends, andinterlocking with the shoulders on the passageway portions.

4. In a contact plug construction, a plug body of resilient materialhaving a fiat slot passageway therethrough, said passageway havingintegral spaced separate parallel portions projecting towards each otherto form a restricted slot passageway intermediate the ends of said fiatslot passageway, said projecting portions having shoulders at each endthereof, and a flat contact prong seated in said flat slot passagewayand extending in alignment therewith, said contact prong having areduced portion intermediate its ends with abrupt shoulders,interlocking with the shoulders on the restricted passageway portions.

5. In a contact plug construction, a plug body of resilient materialhaving a fiat slot passageway therethrough, said passageway havingintegral spaced separate parallel portions projecting towards each otherto form a restricted slot passageway intermediate the ends of said flatslot passageway, said projecting portions having shoulders at each endthereof, and a fiat contact prong seated in said fiat slot passagewayand extending in alignment therewith, said contact prong having aportion of a cross section corresponding to said restricted passagewayintermediate its ends with abrupt shoulders, interlocking with theshoulders on the restricted passageway portions.

6. In a contact plug, a one piece base of resil-' ient flexible materialhaving an upper central recess adapted to receive a cord and two fiatslots extending downwardly therefrom through the plug, said base havingintegral spaced separate parallel portions in each slot projectingtowards each other to form restricted slot passageways intermediate theends of said slots, said projecting portions having shoulders at eachend thereof,

'7. In a contact plug, a one piece base of resilient flexible materialhaving an upper central recess adapted to receive a cord and two flatslots extending downwardly therefrom through the plug, said slots beingspaced equidistant with the diameter of said upper central recess, saidbase having integral spaced separate parallel portions in each slotprojecting towards each other to form restricted slot passagewaysintermediate the ends of said slots, said projecting portions havingshoulders at each end thereof.

8. In a contact plug, a one piece base of resilient'fiexible materialhaving an upper central recess adapted to receive a cord and two fiatslots extending downwardly therefrom through the plug, said base havingintegral spaced separate parallel portions'in each slot projectingtowards each other to form restricted slot passageways in said slots,said projecting portions having shoulders at each end thereof.

WILLIAM P. HERMAN.

